Brake-shoe.



No. 642,295. Patented Jan. 30, I900. J. R. CARDWELL.

BRAKE SHOE.

(Application filed Mar. 20, 1899.

(No Model.)

THE STAT PATENT OFFICE.

JAlllES R. CARDIVELL, OF CHICAGO, ILLINOIS.

BRAKE-SHOE.

SPECIFICATION forming part of Letters Patent No. 642,295, dated January 30, 1900.

Application filed March 20, 1899. Serial No. 709,774. (No model.)

To (LZZ whom it may concern:

Be it known that 1, JAMES R. CARDWELL, a citizen of the United States, and a resident of Chicago, county of Cook, and State of Illinois, have invented certain new and useful Improvements in Brake-Shoes, of which the following, taken in connection with the accompanying drawings, is a specification.

The first of the objects of my invention is the provision of a hardnnetal insert'plate for brake-shoes having cells extending inwardly from its face, the end walls of the cells being oblique to the face of the plate.

Another object of myinvention is the construction of a cast-metal shoe provided with two cellular insert-plates each of which upon one side of the face of the shoe extends for some distance past the center of the shoe. In combination with this arrangement I prefer to employ the fastenin g-1ug arranged back of the middle portion of the shoe, so that the same lug may serve as a strengthening rib or part of the casting.

Another object of myinvention is the provision of abrake-shoe insert formed of a cellular plate of a depth or thickness approximately equal to the thickness of the shoe, the holes in said plate being arranged obliquely with reference to the face of the shoe and with reference to the radial line of the wheel against which the shoe bears. In order to get the best efieot, I prefer to use a plate somewhat resembling an elongated honeycomb in structure, as the honeycomb form disposes the metal to the best advantage, giving the greatest strength with least weight of material, and the elongated form of the cells or holes allows the softer metal which surrounds and incases the insert a better chance to act upon the tread of the wheel.

The above, as well as such other objects as may hereinafter appear, I attain by means of a construction which I have illustrated in preferred form in the accompanying drawings, in which- Figure 1 represents part of a carwheel having my improved brake-shoe applied thereto. Fig. 2 is a face view of the shoe. Fig. 3 is a section on the line 3 3 of Fig. 2. Fig. 4. shows two of the insert-plates which I employ. Fig.

5 shows a modification of my invention in which a single insert-plate is used. Fig. 6 is In the practice of myinvention I first con struct a cellular insert-plate 8, made preferably of cast hardened metal, such as is shown in Fig. t, the outside of this plate being formed so that one can be put in each end of the brake-shoe, with the inner ends of the two extending past each other and past the center of the shoe, as clearly shown in Fig. 2. Any weakness caused by the use of the two plates in the manner shown will be compensated for by the strengthening-rib 9, (shown in Fig. 1,) this rib being made large and arranged near or at the middle of the shoe.

Brakeshoes have been made heretofore with inserts of expanded or perforated sheet metal, and I desire, therefore, that it be understood that the terms cell, cellular, and honeycomb, which I employ, are not intended to cover such forms, but are used as the most suitable words I can find to distinguish my invention from such prior constructions.

In Fig. 1 I have indicated by an arrow one direction of rotation of the wheel. In form ing the cells 10 in the insert I arrange them so that they will stand obliquely to the face of the shoe, and also, of course, obliquely to a radial line extended out from the center of the wheel. By this arrangement I secure, as at the points marked 11, aplurality of cutting or dressing edges of the hard metal, which act to better advantage in dressing the wheel and also serve the purpose of holding in the ground particles of the soft metal of the shoe between the adjacent walls of each of the cells.

In Figs. 2, at, and 5 the openings in the insert-plate are shown as being formed of what may properly be called an elongated honeycomb shape. This particular formation presents a large number of diagonal trimming edges 12, as well as a number of transverse cutting edges 13, and the bearing-point of both of these edges against the periphery of the wheel is constantly shifting in position because of the obliquity of the openings 10.

For example, when the shoe has worn down to a thickness indicated by the dotted line 14:, Fig. 3, the edge of the insert on the face of the shoe, which I have marked 15, will have been moved over to the place marked 16. The purpose of elongating the cells is to give the soft metal which fills the cells and surrounds the insert a better chance to act upon the face of the wheel.

, While the construction which is illustrated in Figs. 2, 3, and 4 is that which I prefer, it is obvious that at least some of the advantages which I aim to obtain by means of my invention may be obtained by the use of a single insert-plate formed with oblique cells such as I have described, and such a construction I have indicated in Fig. 5. It is also obvious that some of the advantages of my invention could be obtained even though the shape of the cells in the insert-plate were materially altered. For example, they may be made cylindrical or round, as shown in Figs. 6 and 7. There are many changes in detail which may be made without departing materially from the spirit of my invention, and I desire to be understood as includin all such immaterial alterations as clearly within the scope of my claims.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is-

1. Acellular brake-shoe insert-plate having the walls of the cells thereof arranged ob- Y liquely with reference to the face of the shoe.

2. A cellular brake-shoe insert-plate having the walls of the cells thereof arranged ob-' liquely with reference to the face of the shoe, the obliquity extending longitudinally.

3. A brake-shoe comprising a cast-metal body having embedded therein a cellular insert-plate, the openings whereof are arranged 40 in a longitudinal oblique direction with reference to the face of the shoe.

4. A brake-shoe comprising a cast-metal body having embedded therein a cellular honeycomb-shaped insert-plate, the openings whereof are. arranged in a longitudinal oblique direction with reference to the face of the shoe.

5. A brake-shoe comprising a cast-metal body having embedded therein a cellular elongated honeycomb-shaped insert-plate, the openings whereof are arranged in a longitudinal oblique direction with reference to the face of the shoe.

6. A brake-shoe containing two cellular insert-plates each of which extends at one side of the face of the shoe for some distance past the center.

7. A brake-shoe containing two cellular insert-plates each of which extends at one side of the face of the shoe for some distance past the center, and a strengthening-lug opposite the point of division between the two insertplates.

8. Allard-metal insert-plate forbrake-shoes having cells extending inwardly from its face, the end Walls of the cells being oblique to the face of the plate.

9. A brake-shoe comprising a cast-metal body having embedded therein a hard-metal insert-plate having cells extending inwardly from its face, the end walls of the cells being oblique to the face of the plate.

JAMES R. OARDIVELL.

Witnesses W. S. -APPLEGATE, PAUL SYNNESTVEDT. 

